> Perhaps... But plyr works only on **basic** data structures, and I referred > to all **possible** data strucures (deliberately); so I stand by my > statement and note that you did not contradict it.
To me the basic structures are vectors, matrices and arrays; lists; and data frames (that these are not mutually exclusive categories). If you master these three basic types, you can master any more complex structure because it must be some combination of the simpler types. Similarly, while each plyr function only works with one of the types, you should be able to deal with any arbitrarily complex data structure by combining multiple functions. This approach doesn't generalise so well with truly recursive data structures (e.g. trees) but these are rarely encountered in their traditional CS form in R. Hadley -- http://had.co.nz/ ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
